chapter 2 compArchi

• Computer components


  • CPU
  • Main memory
  • Input
  • Output
  • Control unit
  • ALU
  • Registers

  
• Computer function


  1. Fetch cycle

  2. Execute cycle
• Instruction cycle


  The processing required for a single instruction
• Program execution halts only if: the machine is turned off, some sort of unrecoverable error occurs, or a program instruction that halts the computer is encountered
• Program counter (PC)


  • Holds the address of the instruction to be fetched next
  • Incremented after each instruction fetch
• Instruction register (IR)


  • The fetched instruction is loaded into a register in the IR
• Interconnection structure


  The collection of paths connecting the various modules
• Bus


  • Point-to-point bus
  • Multipoint bus
• Point-to-point bus


  • Printer cable
  • Network cable
• Multipoint bus


  • Requires addressing signals to identify the desired destination
• System bus


  Interconnects major computer components (processor, memory, I/O)
• System bus


  • Data lines
  • Address lines
  • Control lines
• Data bus


  Provides a path for moving data among system modules
• Address bus


  Designates the source or destination of the data on the data bus
• Control bus


  Transmits both command and timing information among system modules
• Standard buses


  • PCI Express
  • Universal Serial Bus (USB)
  • Integrated Drive Electronics (IDE)
  • Serial Advanced Technology Attachment (SATA)
• IDE


  • Defines the connection between a bus on a computer's motherboard and the computer's disk storage devices using flat ribbon cable
• USB


  • Widely used for peripheral connections
  • Devices are hot-pluggable
• SATA


  • Connects and manages communication between a host device and a storage drive
  • Supports hot plugging
• PCI Express (PCIe)


  • Used to add GPUs, RAID cards, Wi-Fi cards or SSD add-on cards
  • Designed as a high-speed replacement for PCI and AGP standards
• Comparison of buses


  • IDE
  • USB
  • SATA
  • PCIe